The Allerton service was the first tram-to-trolleybus conversion in Bradford. The early trolleybuses had been given a the less-than-enthusiastic reception, largely due to vibration. However, the vehicles purchased to inaugurate this service were more advanced and comfortable and their success here was really the beginning of the growth of modern Bradford system. The service started on 1st June 1929.

The route terminated in Tyrrell Street originally but moved to a stand on Sunbridge Road when the Duckworth Lane trolleybuses were introduced in 1935. It continued along Sunbridge Road, being joined by the Thornton service at City Road as far as Four Lane Ends once that route opened. Here a one-way system was introduced on 8th June 1958 with inbound services using West Park Road. The connection to Duckworth Lane depot along Squire Lane, which survived until the end of Bradford trolleybus, left here. Allerton services continued along Allerton Road, with a loop at Chapel Lane, until the terminus was reached at Prune Park Lane. As can be seen this was quite a rural location.

Services to Allerton ceased on a snowy 27th February 1971, with the last service worked by 791 not in fact reaching the terminus until after midnight. The following day a tour was run to Allerton by 843 and after that this interesting service came to an end.

The additional trolleybuses required for the inauguration of this service led to trolleybuses occupying the main building at Thornbury depot for the first time. The Allerton service was operated from there until the conversion of Duckworth Lane depot in October 1935, when that depot became responsible for operation of all but a few extras.

Service numbers:1930-34 - City to Allerton 40, City to Chapel Lane 411934-66 - City to Allerton 31, City to Chapel Lane 321966-71 - City to Allerton 16